JP2009274067A - Valve unit, fine flow apparatus equipped with the same, and manufacturing method of the valve unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve unit capable of avoiding an increase in cost and capable of preventing the erroneous operation of a valve, a fine flow apparatus equipped with the valve unit and a manufacturing method of the valve unit. <P>SOLUTION: The valve units 100 and 150 are equipped with the first region formed in a lower substrate 15, the second region formed in the lower substrate 15 so as to become more deeply than the first region and being in contact with one side of the first region, the valve substance chamber positioned so as to be superposed on the superposition part being a part of the first region formed in the upper substrate 20 adhering to the lower substrate 15 but so as not to be superposed on the non-superposition part being the remaining part of the first region and the valve substance arranged in the valve substance chamber and heated to flow to the non-superposition part from the valve substance chamber to thereby close the first region. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to microfluidics, and more particularly to a valve unit that controls the flow of fluid, a microfluidic device including the valve unit, and a method for manufacturing the valve unit.

  In general, an apparatus used to perform a biological or chemical reaction by manipulating a small amount of fluid is called a microfluidic apparatus. The microfluidic device includes a microfluidic structure arranged in various shapes of platforms such as chips and disks. The microfluidic structure includes a chamber that can contain a fluid, a channel through which the fluid flows, or a valve that can regulate the flow of the fluid. The chambers, channels, or valves can be arranged in various combinations within the platform.

  In order to perform tests including biochemical reactions on a small chip, a chip-type platform with these microfluidic structures is called a biochip. In particular, the processing and operation of various processes are integrated. An apparatus manufactured so that it can be performed with one chip is called a lab-on-a chip.

  In order to transfer the fluid in the microfluidic structure, a driving pressure is required. However, a capillary pressure may be used as the driving pressure, or a pressure from a separate pump may be used. Recently, a centrifugal force-based microfluidic device that uses centrifugal force by arranging a microfluidic structure on a compact disk-shaped platform has been proposed. This may be referred to as a laboratory CD (Lab CD or Lab-on a CD).

  As an example of the valve provided in the microfluidic device, there is a valve unit disclosed in Patent Document 1 filed by the present applicant. However, this valve unit includes an inlet for injecting a phase change material into the microfluidic device. In order to form the injection port in the microfluidic device, which is an injection, a projection corresponding to the injection port must be formed on the mold, but the resin injected into the mold is separated from the projection and then recombined. As a result, a so-called 'weld line' is formed in the injection. The weld line can cause defects by weakening the rigidity of the microfluidic device. Further, the protrusion formed on the mold cannot smoothly polish the mold, the surface of the injection becomes rough, the flatness is deteriorated, and a step of closing the injection port after the valve is formed is further required. So the cost will increase. In addition, an inclination is also formed on the inner peripheral surface of the injection port due to the pull-out gradient formed on the projection to easily separate the injection from the mold, thereby hindering the operation of the valve.

US patent application Ser. No. 11 / 770,762

  An object of the present invention is to provide a valve unit for controlling the flow of fluid, which can avoid an increase in cost and prevent malfunction of the valve, a microfluidic device including the valve unit, and a method for manufacturing the valve unit. is there.

  A valve unit according to an embodiment of the present invention includes a first region formed in a lower substrate, a second region formed deeper than the first region in the lower substrate and in contact with one side of the first region, The valve material positioned on the upper substrate attached to the lower substrate so as to overlap with the overlapping portion which is a part of the first region and does not overlap with the non-overlapping portion which is the remaining portion of the first region. And a valve substance disposed in the valve substance chamber and heated to flow from the valve substance chamber to the non-overlapping portion to close the first region.

  The valve unit according to the embodiment of the present invention further includes a third region that is formed deeper than the first region on the lower substrate and is in contact with the other side of the first region.

  According to an embodiment of the present invention, the non-overlapping portion of the first region is adjacent to the third region, and the overlapping portion of the first region is adjacent to the second region.

  According to an embodiment of the present invention, the lower substrate and the upper substrate are made of a thermoplastic resin.

  According to an embodiment of the present invention, the valve material includes a phase change material that is in a solid state at room temperature and is melted by being heated.

  According to an embodiment of the present invention, the valve material includes a plurality of fine heating particles dispersed in the phase change material and generating heat by absorbing electromagnetic energy.

  According to an embodiment of the present invention, the fine heating particles are metal oxide particles.

  According to an embodiment of the present invention, the phase change material is a wax, a gel or a thermoplastic resin.

  The valve unit according to an embodiment of the present invention does not provide an inlet for injecting the valve substance into the interior. Therefore, an increase in cost due to the addition of the injection port forming process can be avoided. Further, there is no possibility of malfunction of the valve due to the inlet.

It is a perspective view which shows the microfluidic device by one Embodiment of this invention. It is a perspective view which shows the valve unit by 1st Embodiment of this invention. It is a perspective view which shows the valve unit by 2nd Embodiment of this invention. It is sectional drawing which shows the operation | movement process of the valve unit by 1st Embodiment of this invention sequentially. It is sectional drawing which shows the operation | movement process of the valve unit by 1st Embodiment of this invention sequentially. It is sectional drawing which shows the manufacturing method of the valve unit by 1st Embodiment of this invention sequentially. It is sectional drawing which shows the manufacturing method of the valve unit by 1st Embodiment of this invention sequentially. It is sectional drawing which shows the manufacturing method of the valve unit by 1st Embodiment of this invention sequentially. It is sectional drawing which shows the manufacturing method of the valve unit by 1st Embodiment of this invention sequentially.

  Hereinafter, a valve unit according to an embodiment of the present invention, a microfluidic device including the valve unit, and a method of manufacturing the valve unit will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing a microfluidic device according to an embodiment of the present invention. Referring to FIG. 1, the microfluidic device 10 includes a rotatable disk type platform 11. The platform 11 is formed of a lower substrate 15 and an upper substrate 20 attached to the lower substrate 15. The lower substrate 15 and the upper substrate 20 are made of a thermoplastic resin.

  The microfluidic device 10 includes a chamber 35 for containing a fluid therein, a channel 31 connected to the chamber 35 to provide a passage through which the fluid flows, and a flow of the fluid through the channel 31. Valve units 100 and 150. The microfluidic device 10 is mounted on a spindle motor (not shown) and can rotate at high speed. A mounting through hole 39 is formed at the center of the microfluidic device 10 so as to be mounted on the spindle motor. Due to the rotation of the spindle motor, the fluid left in the chamber 35 or the channel 31 of the microfluidic device 10 is pressurized in a direction toward the outer periphery of the platform 11.

  In the microfluidic device 10, the arrangement of the chamber 35, the channel 31, and the valve units 100 and 150 is determined so as to be suitable for specific applications in the biochemical field such as centrifugation of fluid samples, immune serum reaction, gene analysis, and the like. The That is, the microfluidic device 10 of the present invention is not limited to the arrangement form of the chamber 35, the channel 31, and the valve units 100 and 150 shown in FIG.

  FIG. 2 is a perspective view showing the valve unit according to the first embodiment of the present invention, and FIG. 3 is a perspective view showing the valve unit according to the second embodiment of the present invention. The valve unit according to the first embodiment is a valve unit 100 provided in the middle of the channel 31 of the microfluidic device 10, and the valve unit according to the second embodiment is adjacent to the chamber 35 of the microfluidic device 10. Valve unit 150 may be used.

  Referring to FIG. 2, the valve unit 100 according to the first embodiment includes a first region 101 that is indented downward from the upper side surface of the lower substrate 15, and an indentation that is deeper than the first region 101. A third region 105 that is in contact with a step on one side of the first region 101 and an intaglio formed deeper than the first region 101 so that there is a step on the other side of the first region 101. The second region 107 is provided. Referring to FIG. 4A, the depth D2 of the third region 105 and the second region 107 are equal, and the depth D1 of the first region 101 is shallower. The first region 101, the third region 105, and the second region 107 are provided in the channel 31.

  In addition, the valve unit 100 includes a valve material chamber 109 formed indented upward from the lower surface of the upper substrate 20. The valve material chamber 109 overlaps a part of the first region 101. A part of the first region 101 that overlaps with the valve substance chamber 109 is referred to as an overlapping part 102, and the remaining part of the first region 101 that does not overlap with the valve substance chamber 109 is referred to as a non-overlapping part 103. The valve material chamber 109 contains the valve material V in a cured state. The valve material V is melted after being accommodated in the valve material chamber 109, flows into the non-overlapping portion 103 of the first region 101 and is re-cured, thereby closing the first region 101. The non-overlapping portion 103 is located closer to the third region 105 than the overlapping portion 102.

  The valve material V includes a phase change material that is melted by electromagnetic energy and a plurality of fine heating particles P (see FIG. 4A) that are dispersed in the phase change material and generate heat by absorbing the electromagnetic energy. The phase change material may be a wax. When heated, the wax melts into a liquid state and expands in volume. Examples of the wax include paraffin wax, microcrystalline wax, synthetic wax, and natural wax.

  Meanwhile, the phase change material may be a gel or a thermoplastic resin. For the gel, polyacrylamide, polyacrylate, polymethacrylate, polyvinylamide or the like is employed. In addition, the thermoplastic resin includes COC (cyclic olefin copolymer), PMMA (polymethyl methacrylate), PC (poly carbonate), PS (polystyrene), POM (polypropylene), PFA (polypropylene), PFA (polypropylene), PFA (polypropylene), PFA (polypropylene) , PET (polyethylene terephthalate), PEEK (polyetherethertone), PA (polyamide), PSU (polysulfone), PVDF (polyvinylidenefluoride), and the like are employed.

  The fine exothermic particles P have a diameter of 1 nm to 100 μm so that they can freely pass through the fine channels 31. For example, when the electromagnetic energy is supplied by a method such as irradiation with a laser L, the fine heat-generating particles P have a property that the temperature rapidly rises to generate heat and are uniformly dispersed in wax. The fine exothermic particles P may have a core containing a metal component and a hydrophobic surface structure so as to have such properties. For example, the fine exothermic particles P may have a molecular structure including a core made of Fe and a plurality of surface active components that are bound to the Fe and enclose the Fe.

  Usually, the fine exothermic particles P are stored in a dispersed state in a carrier oil. It is desirable that the carrier oil is also hydrophobic so that the fine exothermic particles P having a hydrophobic surface structure are uniformly dispersed. The valve material V can be manufactured by pouring and mixing the carrier oil in which the fine exothermic particles P are dispersed in the melted phase change material.

The fine exothermic particles P are not limited to the polymer particles mentioned as the example, and may be in the form of quantum dots or magnetic beads. The fine heat-generating particles P may be metal oxide particles such as Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₃ , Fe ₂ O ₃ , Fe ₃ O ₄ or HfO ₂ . On the other hand, the valve material V does not necessarily contain fine exothermic particles, and may be composed of only a phase change material without the fine exothermic particles P.

  The valve unit 100 is a normally closed valve that normally closes the channel 31 and opens the channel 31 by irradiating the valve material V with electromagnetic wave energy. The laser light source 5 is an example of an energy source for irradiating the valve material V with electromagnetic waves, and irradiates the valve material V with energy by irradiating the valve material V with a laser L which is a kind of electromagnetic waves. Supply. The laser light source 5 may include a laser diode (LD).

  4A and 4B are cross-sectional views sequentially illustrating an operation process of the valve unit 100 (see FIG. 2) according to the first embodiment of the present invention. Referring to FIG. 4A, the fluid F flows from the third region 105 toward the second region 107 through the channel 31, but the valve material V hardened in the non-overlapping portion 103 is in the first region. 101 is closed and the fluid F cannot flow. At this time, if the laser light source 5 is used to irradiate the valve material V with the laser L for a while, the fine exothermic particles P contained in the valve material V rapidly generate heat and the phase change material is rapidly heated. . Accordingly, the valve material V is rapidly melted to open the first region 101, and the fluid F can flow from the third region 105 to the second region 107 as shown in FIG. 4B.

  Meanwhile, referring to FIG. 3, the valve unit 150 according to the second embodiment is formed with a first region 151 indented downward from the upper surface of the lower substrate 15 and an indentation deeper than the first region 151. The third region 155 is in contact with a step on one side of the first region 151, and is indented deeper than the first region 151, so that there is a step on the other side of the first region 151. Second region 157. The first region 151 and the second region 157 are provided in the channel 31, while the third region 155 is provided in the chamber 35.

  In addition, the valve unit 150 includes a valve material chamber 159 formed indented upward from the lower surface of the upper substrate 20. Similarly to the valve substance chamber 109 (see FIG. 2) of the valve unit 100 (see FIG. 2) according to the first embodiment, the valve substance chamber 159 overlaps with the overlapping part 152 of the first region 151 and the non-overlapping part 153. Are located so as not to overlap, and the non-overlapping portion 153 is located closer to the third region 155 than the overlapping portion 152. The valve material V is melted after being accommodated in the valve material chamber 159, flows into the non-overlapping portion 153 of the first region 151, and is hardened again, thereby closing the first region 151.

  Similarly to the valve unit 100 according to the first embodiment (see FIG. 2), the valve unit 150 normally closes the channel 31 and irradiates the valve material V with the laser L using the laser light source 5. This is a normal close valve in which the channel 31 is opened. Since the valve material V is the same as the valve material V applied to the valve unit 100 (see FIG. 2) according to the first embodiment, a duplicate description is omitted.

  5A to 5D are cross-sectional views sequentially illustrating a method of manufacturing the valve unit 100 (see FIG. 2) according to the first embodiment of the present invention.

  Referring to FIG. 5A, a lower substrate 15 is first prepared for manufacturing the valve unit 100 (see FIG. 2). The lower substrate 15 is inscribed in a first region 101 indented to a first depth D1 and inscribed in a second depth D2 that is deeper than the first depth D1, and is located on one side of the first region 101. And a second region 107 in contact with the second depth D2 so as to have a step on the other side of the first region 101. The lower substrate 15 can be manufactured by injection molding a thermoplastic resin.

  Referring to FIG. 5B, an upper substrate 20 is prepared for manufacturing the valve unit 100. The upper substrate 20 is thinner than the lower substrate 15 and includes a valve material chamber 109 formed indented. The upper substrate 20 can also be manufactured by injection molding a thermoplastic resin. Since the upper substrate 20 does not include an injection port for injecting the valve material into the microfluidic device 10, a so-called weld line is not formed in the injection molding process. Therefore, the possibility of poor rigidity of the upper substrate 20 is reduced. Further, the process of closing the inlet is not necessary, and the cost can be reduced.

  The valve material chamber 109 is injected with the melted valve material V using a tool such as a dispenser 3 and hardened. As described above, the valve material V is manufactured by mixing a plurality of fine exothermic particles P with a phase change material, and adheres to the valve material chamber 109 when cured.

  Referring to FIG. 5C, a surface of the upper substrate 20 in which the valve material chamber 109 is formed is attached to a surface of the lower substrate 15 in which the first to third regions 101, 105, and 107 are formed. As a method of attaching the upper substrate 20 and the lower substrate 15, for example, a method using a UV adhesive or an ultrasonic fusion method can be used. When the upper substrate 20 and the lower substrate 15 are attached, the valve material chamber 109 is disposed so as to overlap a part of the first region 101. Further, in the first region 101, a non-overlapping portion 103 that does not overlap the valve material chamber 109 is disposed closer to the third region 105 than the overlapping portion 102 that overlaps the valve material chamber 109, The upper substrate 20 and the lower substrate 15 are attached.

  Then, the lower substrate 15 and the upper substrate 20 are heated or energy E is supplied to the valve material V by a method of irradiating a laser to melt the valve material V. Referring to FIG. 5D, a part of the melted valve material V flows into the non-overlapping portion 103 of the first region 101 and remains due to capillary action. The valve substance V left in the non-overlapping portion 103 is re-cured at room temperature to close the first region 101, thereby completing the valve unit 100 (see FIG. 2).

  Since it is difficult to accurately determine the valve material V, a small amount of the valve material V may exceed the boundary of the valve material chamber 109 when the valve material V is injected into the valve material chamber 109. In such a case, when the upper substrate 20 is attached to the lower substrate 15, there is a possibility that the upper substrate 20 and the lower substrate 15 are not firmly attached around the valve material chamber 109. However, since the non-overlapping portion 103 that is closed by the valve material V is formed at a point upstream of the valve material chamber 109 along the flow direction of the fluid F, leakage of the fluid F is prevented. Through actual experiments in which a plurality of valve units 100 according to the first embodiment (see FIG. 2) were formed on the platform and the platform was rotated at 4000 rpm for 5 minutes, no fluid leakage was found in any valve unit.

  Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely an example, and it is understood that various modifications and equivalent other embodiments can be made by those skilled in the art. Will understand. Accordingly, the true protection scope of the present invention should be determined solely by the appended claims.

  The present invention is suitably used, for example, in analysis-related technical fields in the biochemical field.

5 Laser light source,
10 Microfluidic device,
11 platform,
15 Lower substrate,
20 Upper substrate,
31 channels,
35 chambers,
39 mounting through holes,
100, 150 valve unit,
101, 151 first region,
102, 152 overlapping part,
103, 153 non-overlapping part,
105, 155 third region,
107, 157 second region,
109 valve material chamber,
L laser,
P fine exothermic particles,
V Valve material.

Claims (27)

A first region formed in the lower substrate;
A second region formed deeper than the first region on the lower substrate and in contact with one side of the first region;
The valve material positioned on the upper substrate attached to the lower substrate so as to overlap with the overlapping portion which is a part of the first region and does not overlap with the non-overlapping portion which is the remaining portion of the first region. A chamber;
A valve unit comprising: a valve substance that is disposed in the valve substance chamber and heated to flow from the valve substance chamber to the non-overlapping portion and close the first region.   2. The valve unit according to claim 1, further comprising a third region formed deeper than the first region on the lower substrate and in contact with the other side of the first region.   The valve unit according to claim 2, wherein the non-overlapping portion of the first region is adjacent to the third region, and the overlapping portion of the first region is adjacent to the second region.   The valve unit according to claim 1, wherein the lower substrate and the upper substrate are made of a thermoplastic resin.   The valve unit according to any one of claims 1 to 4, wherein the valve substance includes a phase change substance that is in a solid state at room temperature and is melted by being heated.   6. The valve unit according to claim 5, wherein the valve substance includes a plurality of fine heating particles dispersed in the phase change material and generating heat by absorbing electromagnetic energy.   The valve unit according to claim 6, wherein the fine heating particles are metal oxide particles.   The valve unit according to any one of claims 5 to 7, wherein the phase change material is wax, gel, or a thermoplastic resin. A platform including a lower substrate and an upper substrate attached to an upper surface of the lower substrate; a channel formed in the platform for providing a passage through which fluid flows; and controlling a fluid flow through the channel. A valve unit for
The valve unit is formed in the lower substrate and provided in the channel, and a second region formed in the lower substrate deeper than the first region and in contact with one side of the first region. And a third region formed deeper than the first region on the lower substrate and in contact with the other side of the first region, and a part of the first region overlapped on the upper substrate. Are overlapped and positioned so as not to overlap with the non-overlapping portion which is the remaining portion of the first region, and is disposed in the valve material chamber and heated to remove the non-overlapping from the valve material chamber. A microfluidic device comprising: a valve substance that flows into the overlapping portion and closes the first region.   10. The microfluidic device according to claim 9, wherein the valve unit further includes a third region formed deeper than the first region on the lower substrate and in contact with the other side of the first region.   The microfluidic device according to claim 10, wherein the non-overlapping portion of the first region is adjacent to the third region, and the overlapping portion of the first region is adjacent to the second region.   The microfluidic device according to claim 10 or 11, wherein the second region and the third region are provided in the channel.   The microfluidic device according to any one of claims 9 to 12, wherein the lower substrate and the upper substrate are made of a thermoplastic resin.   The microfluidic device according to any one of claims 9 to 13, wherein the valve material includes a phase change material that is in a solid state at room temperature and is melted by absorbing energy.   15. The microfluidic device according to claim 14, wherein the valve material includes a plurality of fine heating particles dispersed in the phase change material and generating heat by absorbing electromagnetic energy.   The microfluidic device according to claim 15, wherein the fine heat generating particles are metal oxide particles.   The microfluidic device according to any one of claims 14 to 16, wherein the phase change material is a wax, a gel, or a thermoplastic resin.   The fine structure according to claim 10 or 11, further comprising a chamber connected to one side of the channel for containing a fluid, wherein the second region or the third region is provided in the chamber. Fluid device.   The microfluidic device according to any one of claims 9 to 18, wherein the platform is configured to be rotatable by a motor. Forming a lower substrate including a first region and a second region formed deeper than the first region and in contact with one side of the first region;
Forming an upper substrate with a valve material chamber;
Injecting and curing the valve material into the valve material chamber;
A surface of the upper substrate on which the valve material chamber is formed is attached to a surface of the lower substrate on which the first and second regions are formed, but the valve material chamber is overlapped with a part of the first region. Attaching the two substrates so as not to overlap with a non-overlapping portion that is the remaining portion of the first region;
Melting the valve material accommodated in the valve material chamber and allowing the valve material to flow into the non-overlapping portion of the first region;
Curing the valve substance that has flowed into the non-overlapping portion, and closing the first region.   21. The method of manufacturing a valve unit according to claim 20, wherein the lower substrate further includes a third region formed deeper than the first region and in contact with the other side of the first region.   The step of attaching the two substrates includes an upper portion of the lower substrate and an upper portion of the first region so that a non-overlapping portion of the first region is adjacent to the third region and an overlapping portion of the first region is adjacent to the second region. The method for manufacturing a valve unit according to claim 20 or 21, further comprising a step of attaching the substrate.   The method for manufacturing a valve unit according to any one of claims 20 to 22, wherein the lower substrate or the upper substrate is formed by molding a thermoplastic resin.   The method for manufacturing a valve unit according to any one of claims 20 to 23, wherein the valve substance is in a solid state at room temperature and includes a phase change substance that is melted by absorbing energy.   25. The method of manufacturing a valve unit according to claim 24, wherein the valve material includes a plurality of fine heat generation particles dispersed in the phase change material and generating heat by absorbing electromagnetic energy.   26. The method of manufacturing a valve unit according to claim 25, wherein the fine heating particles are metal oxide particles.   The method of manufacturing a valve unit according to any one of claims 24 to 26, wherein the phase change material is wax, gel, or a thermoplastic resin.

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